Vitamin B12 & Folate Deficiency Flashcards
Define Vitamin B12 Deficiency?
Having insufficient vitamin B12 to meet demands
What is B12 found in?
B12 is found in meat and animal protein foods
Where does Absorption of Vitamin B12 occur?
In the terminal ileum and requires intrinsic factor
Where is Intrinsic Factor produced?
By gastric parietal cells
What is Pernicious Anaemia?
It is an autoimmune condition involving gastritis, atrophy of all layers of the body and fundus of the stomach and loss of normal gastric glands, parietal and chief cells
What does Pernicious Anaemia lead to?
Lack of intrinsic factor
What does Pernicious Anaemia account for?
80% of megaloblastic anaemia due to impaired Vitamin B12 absorption
What are the gastric causes of Vitamin B12 Deficiency?
Gastrectomy
Atrophic gastritis
What are the intestinal causes of Vitamin B12 Deficiency?
Malabsorption
Ileal resection
Crohn’s affecting the terminal ileum, tropical sprue
What drugs can cause Vitamin B12 Deficiency?
Colchicine
Metformin
What is the most common cause of Vitamin B12 Deficiency?
Inadequate intake (e.g. vegan)
What is the epidemiology of Vitamin B12 Deficiency?
Peak age = 60 yrs
Vegans have a higher risk of dietary Vitamin B12 Deficiency
What are the presenting symptoms of Vitamin B12 Deficiency?
Typical Anaemia symptoms Fatigue Lethargy Dyspnoea Faintness Palpitations Headache Neurological symptoms
What are the neurological symptoms of Vitamin B12 Deficiency?
Paraesthesia
Numbness
Cognitive changes
Visual disturbances
What are the signs of Vitamin B12 Deficiency?
Pallor Heart Failure (can occur with severe anaemia) Glossitis Angular stomatitis Neuropsychiatric signs Neurological signs